CN1443433A - High Performance Compact Loudspeaker - Google Patents

A loudspeaker has first and second ring magnets (1, 2) arranged coaxially, the magnets being connected by a shunt (3) at one end and a limit stop (4, 5) at the other end to concentrate magnetic flux in a cylindrical voice coil gap (G). The shunt and pole piece structures are stacked on top of each other so that the combined magnetic component has an opening (C) through the center. The Voice Coil (VC) floats in the cylindrical magnetic gap, and its driving wire passes through the opening (C) to the other end of the magnet. When used with a cabinet, the speaker membrane (D) is connected through a central opening to a tuned cabinet extending behind the speaker, or the opening is also part of the cabinet, which further controls the overall sound effect. Two shaped pole pieces on the magnet define a shallow voice coil gap with high flux density in which the magnetic field is effectively concentrated.

Compact high performance speaker

The cross reference of related application

The application relates to the 60/214th, No. 689 provisional application case of the U.S. of submission on June 27th, 2000, and requires priority according to the regulation of United States code the 35th chapter the 119th (e).This provisional application case is incorporated this paper in the mode of quoting fully.Background of invention

The present invention relates to a kind of audio tweeter, and be particularly related to a kind of compact loudspeaker.In recent years, the quantity about compact loud speaker application case significantly improves.This part gives the credit to the appearance of a large amount of novel consumption electronic products and personal music electronic playing device, and they need and promote the high-quality acoustics of the use of accessory speakers with the output max volume.Trend to small-sized bookshelf-type or desktop system development has also promoted the use of compact loud speaker, and has become the such audio product of large-scale loud speaker of the similar box work of benchmark for many years, then is eliminated gradually.

For many these class application cases, lightweight and portable be vital.Concerning some, price then is a key factor.Concerning other, then expect by box work or other shells optimize speaker performance.In this case, the require careful consideration structure and the acoustic characteristic of loud speaker and shell.But miniature loudspeaker has caused many technical problems, especially at the low frequency end of wave spectrum, because little film efficient when low frequencies is not high, and has higher natural resonance.Make small size of systems obtain the performance of expectation the compensation method of adopting a whole set of, for example use high drive current, longer lag line coil structures (throw coilconstruction), more powerful magnetic gap, improved thin-film material and novel rack structure.

Therefore, expectation can provide a kind of compact loud speaker of improvement.

Also expectation provides a kind of shell, and it can make the performance of compact loud speaker further improve.

Also expectation provides this loud speaker and design of shell simultaneously, and wherein shell self can be used as a unit and is fit to be placed on rack, metope or other positions, and it does not need a large amount of acoustic engineerings or independent design to consider, just can be suitable with supporting structure.

Summary of the invention

The present invention's loud speaker can be realized target one or more and that other are desired, first and second annular magnets are concentrated and are placed in together in loud speaker, and be connected by the splitter structure of an end and the limit fixed structure of the other end, thus with flux concentrating in cylindrical gap.The same with magnet, splitter and pole piece structure also are annular, and stacked mutually, thereby make the magnetic part after the combination have the perforate of passing central authorities.The voice coil loudspeaker voice coil of loud speaker floats in the cylindrical magnetic gap, and it drives lead and passes central openings and be connected with the loud speaker rear portion.In different embodiment, loudspeaker film links to each other with loud speaker tuned casing afterwards by central openings, and this has further controlled whole acoustics.

According to an aspect of the present invention, the cylindrical magnetic gap between two magnet separates radial polarization and opposite polarity annular magnet.Being positioned at each magnet end face has two T-shaped pole pieces, and they have determined the shallow voice coil gap with high magnetic flux density that mainly is connected with magnetic gap.This structure can be used for using the parts of two annular neodium magnets, it has the external diameter of 25 millimeters and 36 millimeters, obtaining the total magnetic flux density that the per inch voice coil gap surpasses 1.4 teslas (Tesla), and to be lower than total loud speaker weight of 2 ounces (ounce) and the gross energy in the gap be 100 milliwatts (milliwatt) second.Reduced the quality of expensive neodymium like this, the effective simultaneously overall performance that accumulates in effective flux in the gap and improved loud speaker.Specifically, magnet obtains high-energy in very shallow gap, and this makes can be with the strong driving film of little amplitude.The through hole of central authorities plays the guiding loading and unloading in loudspeaker assembly and loud speaker installation process subsequently.Can also utilize perforate in more shallow relatively container, to obtain the level of signification of damping or resonance coupling.This container can be a casing that door is arranged that is installed on that flush or lower panel or the wall.

Description of drawings

Introduce the present invention's illustrative embodiment and relevant example below in conjunction with accompanying drawing.

Fig. 1 has illustrated the high-performance magnetism iron construction of the loudspeaker voice coil according to the present invention;

Figure 1A has illustrated another embodiment of the present invention;

Fig. 2 has illustrated the field vector of magnetic structure among Figure 1A;

Fig. 3 is the magnetic flux density figure of structure interval among Figure 1A;

Fig. 4 A and 4B are respectively the magnetic flux path and the field wire of structure among Figure 1A;

Fig. 5-8 respectively with Figure 1A, 2,3 and 4A corresponding, first characteristics of the solid dish magnet arrangement of structure relatively have been described;

Fig. 9-12A, 12B are corresponding with Figure 1A, 2,3,4A and 4B respectively, and second characteristics of the solid dish magnet arrangement of structure relatively have been described; And

Figure 13 one 16A, 16B are corresponding with Figure 1A, 2,3,4A and 4B respectively, and the 3rd characteristics of the solid dish magnet arrangement of structure relatively have been described.

Detailed Description Of The Invention

The present invention seeks to provide a kind of high efficiency loudspeakers of improvement, and its magnetic minor structure adopts cheap metal parts.Usually adopt permanent magnet in the loud speaker, in less high-performance loud speaker, preferably adopt the rare-earth magnet as neodium magnet.The magnetic minor structure also comprises splitter and pole piece structure, with magnetic field concentration in high magnetic flux gap, in the crack, the cylindrical voice coil loudspeaker voice coil that is additional on the loudspeaker film moves under the effect that adds driving current signal during this time.

In this speaker design process, may be from existing design, according to being regarded as a most important parameter, the optimized design of seeking the New-type loudspeaker magnetic property as magnetic flux, weight, physical depth or price.Although the method is very direct, effectively do not improve and may reduce the performance of other not optimised parameters.The invention provides a kind of structure of innovation, the performance that can improve several parameters simultaneously is to realize a kind of very compact high efficiency loudspeakers.

Applicant's early stage patent and patent application case have been quoted at this, specific as follows: the U.S. the 5th, No. 802191 patent application cases, US application serial No. 09/100,411, US application serial No. 09/439,416, corresponding international application PCT/US99/27011, its US application serial No. 09/639,416 and corresponding international application PCT/US00/22119.Above-mentioned patent and patent application case are incorporated this paper in the mode of quoting fully.

Fig. 1 has represented a specific embodiment of loud speaker 10 of the present invention.Detailed its magnet arrangement 20 and the sketch of film D and voice coil loudspeaker voice coil VC of having demonstrated.For example, voice coil loudspeaker voice coil VC can be entwined on cylindrical spool (as being shaped with polyimides (Kapton) thin slice) by copper or other conductors, and voice coil loudspeaker voice coil VC floats among the magnetic gap G, magnet arrangement 20 with flux concentrating in magnetic gap G.Shown film D is for crossing over the flat board of cylindrical voice coil loudspeaker voice coil VC.The outward flange of this film hangs flexible rubber or polymer belt usually, to form the framework (not shown).But, in other embodiments, can adopt convex or the spill film of crossing over voice coil diameter, or adopt and mainly extend to the flat board or the taper film of voice coil loudspeaker voice coil circumference outside, so that in a bigger framework, install.In this case, with a flexibility but be additional on voice coil loudspeaker voice coil or the film in the endless belt that in-plane has a rigidity, place the center of magnetic gap G to keep voice coil loudspeaker voice coil.Usually at the outward flange of circular cone, another flexible band is additional to film on the speaker frame.

The magnetic flux density that Fig. 3 has drawn and obtained in the gap.As shown in it, the structure of two concentric belt magnet compositions is by 2 millimeters magnetic flux densities of taking advantage of 1 mm clearance to produce 1.4 teslas (Tesla); Total gap energy is 100 milliwatts (milliwatt) seconds.

But driver circuit or lead preferably directly pass perforate.This structure has omitted the voice coil loudspeaker voice coil lead has been inserted the terminal block be positioned on film or the structure centre support (tapered) or the step of terminal pad.Need meticulous processing inside loudspeakers framework because connect in the middle of this, this is a step consuming time in the prior art.

Perforate C also makes the air before and after the loud speaker communicate.Therefore, when film D extends to the whole section of magnet component, its performance will be subjected to the influence of gas column rigidity, and this gas column passes other spaces after perforate enters casing or magnet.When film did not have cover or dome from voice coil loudspeaker voice coil to its excircle extension and at the center, this perforate can alleviate the influence of casing rigidity, and/or draws the sound of casing inside.Therefore, the magnet perforate has realized that acoustical coupling comes the coupled system response, and makes casing have the influence that port alleviates gas column rigidity in the little casing.

Fig. 4 A and 4B described to go in ring among Figure 1A magnetic flux path/field wire of magnet arrangement and device gap area, it has continuous tone and lines independently respectively.This has illustrated and has used small magnet to determine that the magnetic flux path of symmetry is very effective in the magnet component of opening is arranged.

If under the situation that adopts disk magnet, want with Fig. 1-5 in system have identical gap energy, can adopt the structure shown in Figure 13.Magnet thickness among the figure is 12 millimeters, weighs 40 grams, and outer shell and top board make total system weight surpass 100 grams.Figure 15-16B has shown the whole geometry of magnetic flux density, magnetic flux distribution, field wire model and this demonstration example.It is 18.5 millimeters that this structure causes the magnet degree of depth, to such an extent as to can't use in the panel speaker of plane too deeply.The magnet weight that increases has also caused this design more expensive more than the capable design of dicyclo shown in Figure 1.

Therefore, the capable magnet design of dicyclo has high magnetic flux density under the situation of lightweight as can be seen.By relatively, the traditional design with common flux demonstrates too deeply, too heavy and too expensive shortcoming.Loud speaker of the present invention not only effectively concentrates on useful flux in narrow, the shallow voice coil gap, and the central openings of the capable design of dicyclo has also been determined the path of movable voice coil loudspeaker voice coil power line.By saving, reduced the manufacturing cost of loud speaker with driver circuit and the meticulous step that loud speaker internal fixation voice coil loudspeaker voice coil joint is connected.It also makes part dimension littler (not utilizing circumference space on every side to connect up because do not need) simultaneously and has simplified the installation method of casing.The energy that extracts from neodymium has very high efficient, thereby has improved the acoustic efficiency of Linear Driving motor.As mentioned above, porose magnet can also reduce the influence of loudspeaker enclosure rigidity, or makes outside tuning casing and air communication, with weaken or tuning combination loudspeaker/enclosure system in response.

The person of ordinary skill in the field can understand invention disclosed herein and described embodiment with and further changes and improvements, and improve or change and all be within the present invention's the claim or its equivalent scope.